rc.initdiskless revision 128713
1#!/bin/sh 2# 3# Copyright (c) 1999 Matt Dillon 4# All rights reserved. 5# 6# Redistribution and use in source and binary forms, with or without 7# modification, are permitted provided that the following conditions 8# are met: 9# 1. Redistributions of source code must retain the above copyright 10# notice, this list of conditions and the following disclaimer. 11# 2. Redistributions in binary form must reproduce the above copyright 12# notice, this list of conditions and the following disclaimer in the 13# documentation and/or other materials provided with the distribution. 14# 15# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25# SUCH DAMAGE. 26# 27# $FreeBSD: head/etc/rc.initdiskless 128713 2004-04-28 13:18:22Z phk $ 28# 29# REQUIRE: preseedrandom 30# PROVIDE: initdiskless 31# KEYWORD: FreeBSD nojail 32# BEFORE: ipfw 33 34 35# On entry to this script the entire system consists of a read-only root 36# mounted via NFS. The kernel has run BOOTP and configured an interface 37# (otherwise it would not have been able to mount the NFS root!) 38# 39# We use the contents of /conf to create and populate memory filesystems 40# that are mounted on top of this root to implement the writable 41# (and host-specific) parts of the root filesystem, and other volatile 42# filesystems. 43# 44# The hierarchy in /conf has the form /conf/T/M/ where M are directories 45# for which memory filesystems will be created and filled, 46# and T is one of the "template" directories below: 47# 48# base universal base, typically a replica of the original root; 49# default secondary universal base, typically overriding some 50# of the files in the original root; 51# ${ipba} where ${ipba} is the assigned broadcast IP address 52# ${class} where ${class} is a list of directories supplied by 53# bootp/dhcp through the T134 option. 54# ${ipba} and ${class} are typicall used to configure features 55# for group of diskless clients, or even individual features; 56# ${ip} where ${ip} is the machine's assigned IP address, typically 57# used to set host-specific features; 58# 59# Template directories are scanned in the order they are listed above, 60# with each sucessive directory overriding (merged into) the previous one; 61# non-existing directories are ignored. 62# 63# The existence of a directory /conf/T/M causes this script to create a 64# memory filesystem mounted as /M on the client. 65# 66# Some files in /conf have special meaning, namely: 67# 68# Filename Action 69# ---------------------------------------------------------------- 70# /conf/T/M/remount 71# The contents of the file is a mount command. E.g. if 72# /conf/1.2.3.4/foo/remount contains "mount -o ro /dev/ad0s3", 73# then /dev/ad0s3 will be be mounted on /conf/1.2.3.4/foo/ 74# 75# /conf/T/M/diskless_remount 76# The contents of the file points to an NFS filesystem. E.g. if 77# /conf/base/etc/diskless_remount contains "foo.com:/etc", 78# then foo.com:/etc will be be mounted on /conf/base/etc/ 79# If the file contains a pathname starting with "/", then 80# the root path is prepended to it; this allows relocation of 81# the root filesystem withouth changing configuration files. 82# 83# /conf/T/M/md_size 84# The contents of the file specifies the size of the memory 85# filesystem to be created, in 512 byte blocks. 86# The default size is 10240 blocks (5MB). E.g. if 87# /conf/base/etc/md_size contains "30000" then a 15MB MFS 88# will be created. In case of multiple entries for the same 89# directory M, the last one in the scanning order is used. 90# NOTE: If you only need to create a memory filesystem but not 91# initialize it from a template, it is preferrable to specify 92# it in fstab e.g. as "md /tmp mfs -s=30m,rw 0 0" 93# 94# /conf/T/SUBDIR.cpio.gz 95# The file is cpio'd into /SUBDIR (and a memory filesystem is 96# created for /SUBDIR if necessary). The presence of this file 97# prevents the copy from /conf/T/SUBDIR/ 98# 99# /conf/T/SUBDIR.remove 100# The list of paths contained in the file are rm -rf'd 101# relative to /SUBDIR. 102# 103# You will almost universally want to create the following files under /conf 104# 105# File Content 106# ---------------------------- ------------------------------------------ 107# /conf/base/etc/md_size size of /etc filesystem 108# /conf/base/diskless_remount "/etc" 109# /conf/default/etc/rc.conf generic diskless config parameters 110# /conf/default/etc/fstab generic diskless fstab e.g. like this 111# 112# foo:/root_part / nfs ro 0 0 113# foo:/usr_part /usr nfs ro 0 0 114# foo:/home_part /home nfs rw 0 0 115# md /tmp mfs -s=30m,rw 0 0 116# md /var mfs -s=30m,rw 0 0 117# proc /proc procfs rw 0 0 118# 119# plus, possibly, overrides for password files etc. 120# 121# NOTE! /var, /tmp, and /dev will be typically created elsewhere, e.g. 122# as entries in the fstab as above. 123# Those filesystems should not be specified in /conf. 124# 125# (end of documentation, now get to the real code) 126 127dlv=`/sbin/sysctl -n vfs.nfs.diskless_valid 2> /dev/null` 128[ ${dlv:=0} -eq 0 ] && [ ! -f /etc/diskless ] && exit 0 129 130# chkerr: 131# 132# Routine to check for error 133# 134# checks error code and drops into shell on failure. 135# if shell exits, terminates script as well as /etc/rc. 136# 137chkerr() { 138 case $1 in 139 0) 140 ;; 141 *) 142 echo "$2 failed: dropping into /bin/sh" 143 /bin/sh 144 # RESUME 145 ;; 146 esac 147} 148 149# Create a generic memory disk 150# 151mount_md() { 152 /sbin/mdmfs -i 4096 -s $1 -M md $2 153} 154 155# Create the memory filesystem if it has not already been created 156# 157create_md() { 158 if [ "x`eval echo \\$md_created_$1`" = "x" ]; then 159 if [ "x`eval echo \\$md_size_$1`" = "x" ]; then 160 md_size=10240 161 else 162 md_size=`eval echo \\$md_size_$1` 163 fi 164 mount_md $md_size /$1 165 /bin/chmod 755 /$1 166 eval md_created_$1=created 167 fi 168} 169 170# DEBUGGING 171# 172# set -v 173 174# Figure out our interface and IP. 175# 176bootp_ifc="" 177bootp_ipa="" 178bootp_ipbca="" 179if [ ${dlv:=0} -ne 0 ] ; then 180 iflist=`ifconfig -l` 181 for i in ${iflist} ; do 182 set -- `ifconfig ${i}` 183 while [ $# -ge 1 ] ; do 184 if [ "${bootp_ifc}" = "" -a "$1" = "inet" ] ; then 185 bootp_ifc=${i} ; bootp_ipa=${2} ; shift 186 fi 187 if [ "${bootp_ipbca}" = "" -a "$1" = "broadcast" ] ; then 188 bootp_ipbca=$2; shift 189 fi 190 shift 191 done 192 if [ "${bootp_ifc}" != "" ] ; then 193 break 194 fi 195 done 196 # Insert the directories passed with the T134 bootp cookie 197 # in the list of paths used for templates. 198 i="`/sbin/sysctl -n kern.bootp_cookie`" 199 [ "${i}" != "" ] && bootp_ipbca="${bootp_ipbca} ${i}" 200 201 echo "Interface ${bootp_ifc} IP-Address ${bootp_ipa} Broadcast ${bootp_ipbca}" 202fi 203 204# Figure out our NFS root path 205# 206set -- `mount -t nfs` 207while [ $# -ge 1 ] ; do 208 if [ "$2" = "on" -a "$3" = "/" ]; then 209 nfsroot="$1" 210 break 211 fi 212 shift 213done 214 215# The list of directories with template files 216templates="base default ${bootp_ipbca} ${bootp_ipa}" 217 218# The list of filesystems to umount after the copy 219to_umount="" 220 221# If /conf/diskless_remount exists, remount all of /conf. This allows 222# multiple roots to share the same conf files. 223if [ -d /conf -a -f /conf/diskless_remount ]; then 224 nfspt=`/bin/cat /conf/diskless_remount` 225 if [ `expr "$nfspt" : '\(.\)'` = "/" ]; then 226 nfspt="${nfsroot}${nfspt}" 227 fi 228 mount_nfs $nfspt /conf 229 chkerr $? "mount_nfs $nfspt /conf" 230 to_umount="/conf" 231fi 232 233# Resolve templates in /conf/base, /conf/default, /conf/${bootp_ipbca}, 234# and /conf/${bootp_ipa}. For each subdirectory found within these 235# directories: 236# 237# - calculate memory filesystem sizes. If the subdirectory (prior to 238# NFS remounting) contains the file 'md_size', the contents specified 239# in 512 byte sectors will be used to size the memory filesystem. Otherwise 240# 8192 sectors (4MB) is used. 241# 242# - handle NFS remounts. If the subdirectory contains the file 243# diskless_remount, the contents of the file is NFS mounted over 244# the directory. For example /conf/base/etc/diskless_remount 245# might contain 'myserver:/etc'. NFS remounts allow you to avoid 246# having to dup your system directories in /conf. Your server must 247# be sure to export those filesystems -alldirs, however. 248# If the diskless_remount file contains a string beginning with a 249# '/' it is assumed that the local nfsroot should be prepended to 250# it before attemping to the remount. This allows the root to be 251# relocated without needing to change the remount files. 252# 253for i in ${templates} ; do 254 for j in /conf/$i/* ; do 255 # memory filesystem size specification 256 # 257 subdir=${j##*/} 258 if [ -d $j -a -f $j/md_size ]; then 259 eval md_size_$subdir=`cat $j/md_size` 260 fi 261 262 # remount 263 # 264 if [ -d $j -a -f $j/remount ]; then 265 nfspt=`/bin/cat $j/remount` 266 $nfspt $j 267 chkerr $? "$nfspt $j" 268 to_umount="${to_umount} $j" # XXX hope it is really a mount! 269 fi 270 271 # NFS remount 272 # 273 if [ -d $j -a -f $j/diskless_remount ]; then 274 nfspt=`/bin/cat $j/diskless_remount` 275 if [ `expr "$nfspt" : '\(.\)'` = "/" ]; then 276 nfspt="${nfsroot}${nfspt}" 277 fi 278 mount_nfs $nfspt $j 279 chkerr $? "mount_nfs $nfspt $j" 280 to_umount="${to_umount} $j" 281 fi 282 done 283done 284 285# - Create all required MFS filesystems and populate them from 286# our templates. Support both a direct template and a dir.cpio.gz 287# archive. Support dir.remove files containing a list of relative 288# paths to remove. 289# 290# The dir.cpio.gz form is there to make the copy process more efficient, 291# so if the cpio archive is present, it prevents the files from dir/ 292# from being copied. 293 294for i in ${templates} ; do 295 for j in /conf/$i/* ; do 296 subdir=${j##*/} 297 if [ -d $j -a ! -f $j.cpio.gz ]; then 298 create_md $subdir 299 cp -Rp $j/* /$subdir 300 fi 301 done 302 for j in /conf/$i/*.cpio.gz ; do 303 subdir=${j%*.cpio.gz} 304 subdir=${subdir##*/} 305 if [ -f $j ]; then 306 create_md $subdir 307 echo "Loading /$subdir from cpio archive $j" 308 (cd / ; /stand/gzip -d < $j | /stand/cpio --extract -d ) 309 fi 310 done 311 for j in /conf/$i/*.remove ; do 312 subdir=${j%*.remove} 313 subdir=${subdir##*/} 314 if [ -f $j ]; then 315 # doubly sure it is a memory disk before rm -rf'ing 316 create_md $subdir 317 (cd /$subdir; rm -rf `/bin/cat $j`) 318 fi 319 done 320done 321 322# umount partitions used to fill the memory filesystems 323[ -n "${to_umount}" ] && umount $to_umount 324